Research Nicky Staes

Abstract

Despite their close phylogenetic relationship and phenotypic similarities, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes), humans closest living relatives, show a distinctive behavioral divergence. Bonobos show a remarkable reduction in aggressiveness, which is hypothesized to co-evolve with a larger suit of correlated traits, the "domestication syndrome". As selection targets gene variants that lower aggression, simultaneous alterations are seen in other behavioral traits. While reactive behaviors (aggression, anxiety) decrease, prosocial behaviors (grooming, play, sex) simultaneously increase. Which genes were targeted remains largely unknown. Here I investigate the role of serotonin as a potential modulator of the behavioral divergence in Pan, a neurotransmitter with a well-documented role in the regulation of both reactive and prosocial behaviors. I will systematically compare aggression, anxiety, grooming, sex and play between the two species and investigate to what extent variation in four largely unstudied serotonergic genes impacts behavioral variation within and between the two species. In addition, I will examine a novel and largely unexplored pathway by expanding our investigation to the hologenome, or the combined set of genomes of the host and its cohabiting gut microbes, the gut microbiome (GM). The GM directly impacts host social behavior through interaction with the gut-brain axis, and plays an important regulatory role in serotonergic signaling.

Researcher(s)

• Promoter: Eens Marcel
• Fellow: Staes Nicky

Research team(s)

• Behavioural Ecology & Ecophysiology

Project website

Project type(s)

• Research Project

Abstract

It has been known for a relatively long time that the microbes living in our gut play an important role in regulating our physical and mental health. However, recent literature emphasizes the potentially major role of the gut microbiome in the regulation of brain function and behavior. Gut microbes play an important role in the development and regulation of behavior and cognition, giving rise to a connection between the brain and the gut, also known as the gut-brain axis. Conversely, the social behavior of the host itself will directly influence the composition of the gut microbiome, indicating the axis is bidirectional. To date, very little is known about the gut-brain axis in animals, especially in non-human primates. Great apes are of particular interest, since they form an excellent study system to investigate the evolution of the gut-brain axis in humans because of their high evolutionary relatedness. Bonobos in particular form an interesting model-species due to their high overlap in socio-cognitive skills with humans, but surprisingly, their gut microbiome remains largely unstudied. Therefore, the aim of this study is to characterize the bonobo gut microbiome and to investigate which factors drive interindividual variation in gut microbiome composition and diversity, including behavior. Moreover, I will perform behavioral observations combined with experimental microbiome manipulations to closely examine the impact and dependence of the microbiome on bonobo sociality.

Researcher(s)

• Promoter: Eens Marcel
• Co-promoter: Staes Nicky
• Fellow: Torfs Jonas

Research team(s)

• Behavioural Ecology & Ecophysiology

Project type(s)

• Research Project

Abstract

The difference in cognition between humans and apes is not simply a greater degree of general intelligence, but rather a quantitative difference in social cognition. Social cognition comprises the ability to understand and respond to social responses of others. This concept includes social skills related to self-knowledge and theory of mind, which indicates the ability to understand the emotions and behavior of a person from their perspective. This project focuses on our closest living evolutionary relatives: bonobos and chimpanzees. These two species diverged from the human lineage only 5-8 mya. This makes them keystone species for investigating our own evolutionary past and identifying unique human traits. Bonobos and chimpanzees diverged from each other between 1-2 mya, but show considerable differences in social cognition. Studies in bonobos have shown that they have higher social sensitivity and are better at tasks that require social tolerance and cooperation. To date, very little is known about the mechanisms behind these behavioral differences. Therefore, this study aims to contribute to our understanding of the evolutionary origins of human sociality by studying the genetic mechanism underlying these differences in these two closely related ape species. More specifically, I aim to investigate variation in candidate genes that play an important role in the regulation of the social brain, and how they impact sociability, cooperation and social tolerance.

Researcher(s)

• Promoter: Eens Marcel
• Co-promoter: Stevens Jeroen
• Fellow: Staes Nicky

Research team(s)

• Behavioural Ecology & Ecophysiology

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand KMDA. UA provides KMDA research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Eens Marcel
• Co-promoter: Stevens Jeroen
• Co-promoter: Stevens Jeroen
• Fellow: Staes Nicky

Research team(s)

• Behavioural Ecology & Ecophysiology

Project type(s)

• Research Project